With the development of display technology, transparent display technology has been more and more applied in the daily life. As the transparent display technology, taken as a brand-new display technology, allows the observer to see the rear area through a display screen, the transparent display technology significantly improves the efficiency and convenience of man-machine interaction, and hence is applied in more and more fields, for instance, being applied in various fields such as vending machines, billboards, display windows, car head-up displays and laptops.